Gesture_PAJ7620 & midi

nickrobinson · January 21, 2022, 12:44pm

I have a Gesture_PAJ7620 connected to a nano. The idea is to send midi commands related to the gestures. However, it's transmitting sysex message all the time - presumably output from the sensor? The gesture works fine when sending text messages. The same board sends midi properly without the gesture. Any ideas?

#include <MIDI.h>
#include <midi_Defs.h>
#include <midi_Message.h>
#include <midi_Namespace.h>
#include <midi_Settings.h>

#include <Wire.h>
#include "paj7620.h"

MIDI_CREATE_DEFAULT_INSTANCE();

#define GES_REACTION_TIME   500       // You can adjust the reaction time according to the actual circumstance.
#define GES_ENTRY_TIME      800       // When you want to recognize the Forward/Backward gestures, your gestures' reaction time must less than GES_ENTRY_TIME(0.8s). 
#define GES_QUIT_TIME     1000

void setup() {
MIDI.begin(1);   
}

void loop() {
  uint8_t data = 0, data1 = 0, error;
  error = paj7620ReadReg(0x43, 1, &data);       // Read Bank_0_Reg_0x43/0x44 for gesture result.
  if (!error) {
    switch (data) {               // When different gestures be detected, the variable 'data' will be set to different values by paj7620ReadReg(0x43, 1, &data).
      case GES_RIGHT_FLAG:
        MIDI.sendProgramChange(1, 1);
        delay(GES_QUIT_TIME);
        break;
      case GES_LEFT_FLAG:
        MIDI.sendProgramChange(2, 1);
        delay(GES_QUIT_TIME);
        break;
      case GES_UP_FLAG:
        MIDI.sendProgramChange(3, 1);
        delay(GES_ENTRY_TIME);
        break;
      case GES_DOWN_FLAG:
        MIDI.sendProgramChange(4, 1);
        delay(GES_QUIT_TIME);
        break;
      case GES_FORWARD_FLAG:
        MIDI.sendProgramChange(5, 1);
        delay(GES_QUIT_TIME);
        break;
      case GES_BACKWARD_FLAG:
        MIDI.sendProgramChange(6, 1);
        delay(GES_QUIT_TIME);
        break;
      case GES_CLOCKWISE_FLAG:
        MIDI.sendProgramChange(3, 1);
        break;
      case GES_COUNT_CLOCKWISE_FLAG:
        MIDI.sendProgramChange(8, 1);
        break;
      default:
        paj7620ReadReg(0x44, 1, &data1);
        if (data1 == GES_WAVE_FLAG) {
          MIDI.sendProgramChange(9, 1);
        }
        break;
    } // end switch
  } // end if no error
  delay(100);
} // end loop

alto777 · January 21, 2022, 1:13pm

What is sending system message to whom?

device -> Arduino -> [MIDI message] -> ??

Or do you mean you get multiple outputs from one gesture? Maybe there needs to be an acknowledgement or clearing of the gesture device.

Maybe a bit more detail and a diagram, even a celly of a hand drawn picture woukd help us along.

a7

nickrobinson · January 21, 2022, 1:57pm

Sorry to be vague. It's sending midi to the input of my focusrite audio interface, then I read that input using midiOX

Here's a fritzing

nickrobinson · January 21, 2022, 2:01pm

what it's currently sending
Screenshot_1

alto777 · January 21, 2022, 3:29pm

OK, the Arduino sends MIDI.

The only lines that do this look like

MIDI.sendProgramChange(9, 1);

Are those SYSEX messages?

Temporarily remove the default case (comment it out).

Increase the delay to 1000: do you now get one message a second whether you do a gesture or not?

I think the device is always saying “no error” but that doesn’t always mean a new gesture has been recognized.

But I will admit this is “deserted island” debugging for me: what I would try knowing almost nothing about it.

So a few stabs in the dark while we wait for the heavies to finish breakfast or whatever is keeping them.

I’ll go look into the gesture device. Looks cool. And no problem with using an alternate part. We can deal.

a7

nickrobinson · January 21, 2022, 4:04pm

removed the default case, tried other midi messages

MIDI.sendControlChange(61, 0, 1);

no diff. My logic is that if no gestures are detected, it shouldn't send anything but there's a stream of messages.

Thanks for your support, it really helps not to be alone!

alto777 · January 21, 2022, 4:50pm

OK, more detail. Always say too much!

These messages should be happenig only once a second. dealy(1000);. Did that slow down the pace?

And they should only be the ones you have in the code.

Is there anything else around going on MIDI-wise that you might be confusing for message you create?

I'd add some printing to look at what's happening. Does the stream repeat the same message? Can you decode the stream to see what the messages are?

Have you tried finding and running an example?

Sry, shooting in the dark, just stuff I'd try.

a7

alto777 · January 21, 2022, 5:46pm

Try this. I didn't compile it, but it should or nearly. edit: one typo. It compiles, but I have no gesture device, so over to you.

I just

shut off anything that might have sent a MIDI package.

and

added some printing so we can see the flow

This should just tell you about the things you picking up from the sensor.

Divide and conquer.

# include <MIDI.h>
# include <midi_Defs.h>
# include <midi_Message.h>
# include <midi_Namespace.h>
# include <midi_Settings.h>

# include <Wire.h>
# include "paj7620.h"

MIDI_CREATE_DEFAULT_INSTANCE();

# define GES_REACTION_TIME   500       // You can adjust the reaction time according to the actual circumstance.
# define GES_ENTRY_TIME      800       // When you want to recognize the Forward/Backward gestures, your gestures' reaction time must less than GES_ENTRY_TIME(0.8s). 
# define GES_QUIT_TIME     1000

void setup() {
  Serial.begin(115200);
  Serial.println("Hello Gesture MIDI World!\n");

  //  MIDI.begin(1);
}

void loop() {
  uint8_t data = 0, data1 = 0, error;
  error = paj7620ReadReg(0x43, 1, &data);       // Read Bank_0_Reg_0x43/0x44 for gesture result.
  if (!error) {
    switch (data) {               // When different gestures be detected, the variable 'data' will be set to different values by paj7620ReadReg(0x43, 1, &data).
      case GES_RIGHT_FLAG:
  //        MIDI.sendProgramChange(1, 1);
        Serial.print(" GES_RIGHT_FLAG "); Serial.println(data);
        delay(GES_QUIT_TIME);
        break;
      case GES_LEFT_FLAG:
  //        MIDI.sendProgramChange(2, 1);
        delay(GES_QUIT_TIME);
        Serial.print(" LEFT "); Serial.println(data);
        break;
      case GES_UP_FLAG:
   //        MIDI.sendProgramChange(3, 1);
        delay(GES_ENTRY_TIME);
        Serial.print(" GES_UP_FLAG "); Serial.println(data);
        break;
      case GES_DOWN_FLAG:
   //        MIDI.sendProgramChange(4, 1);
        delay(GES_QUIT_TIME);
        Serial.print(" GES_DOWN_FLAG "); Serial.println(data);
        break;
      case GES_FORWARD_FLAG:
   //        MIDI.sendProgramChange(5, 1);
        delay(GES_QUIT_TIME);
        Serial.print(" GES_FORWAWRD_FLAG "); Serial.println(data);
        break;
      case GES_BACKWARD_FLAG:
   //        MIDI.sendProgramChange(6, 1);
        delay(GES_QUIT_TIME);
        Serial.print(" GES_BACKWAWRD_FLAG "); Serial.println(data);
        break;
      case GES_CLOCKWISE_FLAG:
   //        MIDI.sendProgramChange(3, 1);
        Serial.print(" GES_CLOCKWISE_FLAG "); Serial.println(data);
        break;
      case GES_COUNT_CLOCKWISE_FLAG:
   //        MIDI.sendProgramChange(8, 1);
        Serial.print(" GES_ANTI_CLOCKWISE_FLAG "); Serial.println(data);
        break;
      default:
        Serial.print(" default "); Serial.print(data);
        paj7620ReadReg(0x44, 1, &data1);
        if (data1 == GES_WAVE_FLAG) {
     //        MIDI.sendProgramChange(9, 1);
          Serial.print(" default "); Serial.println(data);
        }
        break;
    } // end switch
  } // end if no error
  delay(1000);
} // end loop

a7

nickrobinson · January 21, 2022, 7:26pm

I started with this code and it works fine. I assumed that simply replacing Serial.print with midi out code would work, but something else is going on. As I say, gesture code works, midi code works, combining the two doesn't ;(

alto777 · January 21, 2022, 7:31pm

I don’t know if you left the Serial.print lines in place.

If you did, does the flow seem to change?

And can you list the test MIDI-only code that works? How are you forming the content of those messages?

There is nothing evident to suggest it shouldn’t work like you think.

Oh, wait, I see you are re-using the hardware serial port, so you can’t do both at once.

Do you know if you can move MIDI to a software serial port?

Do you have an Arduino with more than one hardware serial port?

Maybe you could move the debug printing onto a software serial port.

Sry, combination of hand waving and straw grasping here.

a7

nickrobinson · January 21, 2022, 9:04pm

That sounds a possible diagnosis. Will look into software serial. But the gesture is connected to A4 and A5 - does this create a second serial port that will transmit from the tx pin??

alto777 · January 21, 2022, 9:59pm

No, the gesture device is communicating over I2C. Using the I2C pins.

a7

nickrobinson · January 21, 2022, 11:03pm

And they are not independent of the standard tx pin? I'm only transmitting midi and only receiving gesture data but the two seem connected.

Thanks for all this help - I'll get there in the end

Grumpy_Mike · January 22, 2022, 1:48am

Is this audio interface expecting to receive MIDI messages?
If so it is expecting them at 31.25KHz, so your serial interface must be set to 31250 baud using the serial begin call.

You will not be able to see messages at this speed because the serial monitor can’t be set at this speed. So you loose the ability to use the serial print for debug messages,

Also not only has the speed got to be right but the signal needs to be the correct form and polarity. Your attempt at a diagram gives me no confidence that you are wiring the output correctly.

Can you please show how your TX is wired from the Arduino to the socket. Correct wiring would involve resistors.

See this page
https://www.personal.kent.edu/~sbirch/Music_Production/MP-II/MIDI/midi_physical_layer.htm

alto777 · January 22, 2022, 3:12am

No, they shouldn't interfere with each other.

Can you read #7 again, I don't think you've posted a tiny program that shows you can just directly send/receive at the focusrite the same MIDI command(s) you are trying to gate with gestures.

That is a tiny program that has only the MIDI. No mention or use of the gesture device.

And another that does just the gesture reception and Serial.print of what you are getting from it. No MIDI stuff.

If I read correctly, you have done both and if I am reading carefully I see neither. Sketch.

I know they are simple and work, but there may be a clue.

Also: I do not know but you should probably, or learn: can the MIDI serial comms work using software serial ports?

a7

nickrobinson · January 22, 2022, 9:35am

the midi library takes care of that.

As it does, see my earlier fritzing....

nickrobinson · January 22, 2022, 9:41am

the working midi test code

#include <MIDI.h>
#include <midi_Defs.h>
#include <midi_Message.h>
#include <midi_Namespace.h>
#include <midi_Settings.h>
MIDI_CREATE_DEFAULT_INSTANCE();

void setup() 
{
MIDI.begin(1);   
}

void loop() 
{
MIDI.sendNoteOn(55,127,1);  // Send a Note for testing purposes
delay(500);		// Wait for a second
MIDI.sendNoteOff(55,0,1);   // Stop the note 
}

and the (working) gesture only code

#include <Wire.h>
#include "paj7620.h"
#define GES_REACTION_TIME   500       // You can adjust the reaction time according to the actual circumstance.
#define GES_ENTRY_TIME      800       // When you want to recognize the Forward/Backward gestures, your gestures' reaction time must less than GES_ENTRY_TIME(0.8s). 
#define GES_QUIT_TIME     1000

void setup() {
  uint8_t error = 0;

  Serial.begin(9600);
  Serial.println("\nPAJ7620U2 TEST DEMO: Recognize 9 gestures.");

  error = paj7620Init();      // initialize Paj7620 registers
  if (error) {
    Serial.print("INIT ERROR,CODE:");
    Serial.println(error);
  } else {
    Serial.println("INIT OK");
  }
  Serial.println("Please input your gestures:\n");
}

void loop() {
  uint8_t data = 0, data1 = 0, error;

  error = paj7620ReadReg(0x43, 1, &data);       // Read Bank_0_Reg_0x43/0x44 for gesture result.
  if (!error) {
    switch (data) {               // When different gestures be detected, the variable 'data' will be set to different values by paj7620ReadReg(0x43, 1, &data).
      case GES_RIGHT_FLAG:
        Serial.println("Right");
        delay(GES_QUIT_TIME);
        break;
      case GES_LEFT_FLAG:
        Serial.println("Left");
        delay(GES_QUIT_TIME);
        break;
      case GES_UP_FLAG:
        Serial.println("Up");
        delay(GES_ENTRY_TIME);
        break;
      case GES_DOWN_FLAG:
        Serial.println("Down");
        delay(GES_QUIT_TIME);
        break;
      case GES_FORWARD_FLAG:
        Serial.println("Forward");
        delay(GES_QUIT_TIME);
        break;
      case GES_BACKWARD_FLAG:
        Serial.println("Backward");
        delay(GES_QUIT_TIME);
        break;
      case GES_CLOCKWISE_FLAG:
        Serial.println("Clockwise");
        break;
      case GES_COUNT_CLOCKWISE_FLAG:
        Serial.println("anti-clockwise");
        break;
      default:
        paj7620ReadReg(0x44, 1, &data1);
        if (data1 == GES_WAVE_FLAG) {
          Serial.println("wave");
        }
        break;
    } // end switch
  } // end if no error
  delay(100);
} // end loop

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Gesture_PAJ7620 & midi

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